Carburetor



2 Sheets-Sheet l GARBURETOR R. F. ENSIGN ET AL Filed MayxlQ- 1921 Apn'l1, 1930.

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R. F. ENSIGN ET AL GARBURETOR April 1, 1930.

Filed May 19, 1921 2 Sheets-Shet 2 v wm, 1...... bkk, im Il E I i. 7. MO .fo//pW/m//WJt/W/mw; d, 0/ m4: Z ,.7 5 wm zl/I//M rm 7 V W 6 f I 8 av4r d 3 M nal 3 2 YM af .j s 7 l e l, 7: awa@ ITM/w wl :n/v/ m n W'A/H/f\\\ www m i ROY FRANCIS nNsIGN AND Patented Apr. 1, 1930 UNITEDSTATES PATENT OFFICE ORVILLE HIRAM ENSIGN, OF PASADENA, CALIFORNIA,

ASSIGNORS TO ENSIGN CARBURETOR COMPANY, OF LOS ANGELES, CALIFORNIA, A

CORPORATION OF CALIFORNIA CARBURETOR Application iiled May 19,

An object of this invention is to provide an easy-starting compact,efficient carburetor of moderate cost.

This invention includes a new application of air for proportioning fueland air and consists in creating a whirl of air around the fuel deliveryorifice and involves a new principle of directing the air to form themixture; and in this respect the air passages and chambers of thecarburetor are so constructed as to produce a whirl in the air as itpasses through the carburetor and thereby produce a maximum depressionfor proportioning purposes, with a minimum resistance to the mixtureflow through the carburetor.

An object is to avoid the heavy depression in manifolds during engineoperation and hence to increase the volumetric efficiency of the engine.This is accomplished by creating a whirl of air in the mixing chamberand withdrawing the mixture from the periphery of such whirl instead ofat the center of such whirl. y

We have discovered that the foregoing objects can be obtained byproviding the carburetor with a mixing chamber of a substantiallycircular form with tangential inlet for the air and a tangential outletfor the mixture.

Another feature of the invention is effectually utilizing the depressionbeyond the throttle for controlling the mixture during idling and lowspeedfoperation by applying on the fuel orifice through a by-pass thefull depression eective beyond the throttle.

This is accomplished by so constructing the carburetor that a depressionequal to that portion of the depression obtained through the by-pass andwhich would be otherwise lost due to drawing atmospheric air through theair intalre into the by-pass, is applied to the .fuel orifice by themeans used for creating the depression in the mixture chamber duringpower operation. We thereby make use of one fuel orifice under twoseparate controls for and power.

Other objects, advantages and features of invention may appear from theaccompanying drawings, the subjoined detail description and the appendedclaims.

1921. Serial No. 470,829.

The accompanying drawings illustrate the invention.

Figure l is a plan view of a whirlpool type carburetor constructed inaccordance with this invention.

Fig. 2 is a vertical section on irregular line 'mL-m2, Fig. 1,illustrating the means for malring adjustments for both the idling andpower mixtures.

Fig. 3V is an enlarged horizontal sectional detail on line m3, Figs. 2,6 and 7.

Fig. 4 is a horizontal section on line indicated at m4, Figs. 2, 6 and 7'Fig 5 is a horizontal section on line m5,

Figs. 2 and 6.

Fig'. 6 is a vertical section on line so, Figs. l and 5., and vshows theducts leading the air to both of the adjustment means.

Fig. 7 is an enlarged fragmental axial section of the well and partsadjacent thereto.

In Figs. l and 2 the throt le is shown wide open. In Fig. 5 it is shownin the idling position. lnFig. 6 the starting choke is slightlydisplaced from the'position shown in Fig. l, for convenience'of thedraftsman.

In Fig. 3 the adjusting sleeve is shown turned to a dierent'positionfrom that in the other figur-es. Y

For. convenience of description we shall use the word depressionto meanthe drop of air pressure inthe carburetor below that of the externalatmospheric pressure, and the amount of depression stated can always bereferred to as the height of a column of gasoline.

The main structure of prises the constant level fuel supply chamber land the chambered main` body 2. These two parts are held together by anut 8 screwed onto and closing the lower end of a well extension 4 thatlextends downward from the center of the practically unobstructed cirthecarburetor comcular or cylindrical fuel and air proportionconsists of abore in the extension 4.

an outlet 9 both of which extend tangentially outward from the peripheryof the mixing chamber, to supply air to and to discharge mixture fromsaid mixing chamber under the suction of an internal combustion engine7not shown, which is connected to the throttle flange f10 by means ofengine manifold 1l.

The inlet 8 may enter the mixing chamber in any desired relation to theoulet 9. lt is so positioned that in operationv a violent whirl actionwill be produced in the mixing chamber when engine suction is applied at11.

The construction shown is now considered most convenient for mostautomobile engines with a horizontal carburetor, and in this cas boththe inlet and outlet of the mixing chamber are on the same horizontalplane. The fuel enters chamber 1 through the fuel connection 12 and iscontrolled by the float valve 13 operated by means of the float lever 14and float 15 to maintain the fuel at the constant level point 16. j

The adjustable fuel orifice 17 leads from the fuel supply chamber intothe well 1S that The means for adjusting the fuel orilice 17 are shownconsisting of a tube 19 provided at the top with a milled head 20 forconvenience in handling, and screwed into a boss 21 which is castintegral with the top of the mixing chamber 5.

The tube 19 lits snugly into the lower part of the well 18; and by meansof the threaded portion, said tube can be screwed up and down to openand close the fuel orifice 17.

The tube 19 above the floor Q3 of the mixing chamber` provided with jetholes 24 leading from the bore 25 of the adjusting tube 19, fordelivering fuel into the mixing chamber 5 at approximately right anglesto thc axis of rotation of the whirling circular body of air. Vit-hinthe adjusting tube 19 is tted an accelerating tube 29 which i suppliedwith air from the air inlet out.,. .e the starting choke Q7, through themedium of the duct 28 and the annular passage 28 through port 29 leadinginto the bore of the accelerating tube Underload, air flowing from theair inlet Q6, through the mixing chamber inlet 8, produces a whirlwithin the mixing chamber 5, which causes, around the adjusting tube 19,at the center of themixing chamber and at the axial center of saidwhirl, a market deinession; thereby ea :sing fuel to be drawn throughthe fuel orifice 17, the well 18 and bore 25 of the adjusting tube 197and out through the jet holes 24 into the mixing chamber 5, where it istalren up by the violent- 1y whirling air and is mixed therewith. Undervery light load and idling condition, the whirl depression alone notenough to lift fuel from the' level 16 tothe mixing chaluber 5.

The throttle disk 30 is carried by the shaft 31 and may be operatedthrough the medium of the lever 32 to open and close the throttle barrel33 to meet conditions of variable load. Upon closingthe throttle to thcidling` position, a great depression, amountin in most eases to one-halfatmospheric jn'eisure, occurs beyond the throttle in the engineinanifold.

This full clli'cct of this depresion through a duct, passage or b y-pass34 is utilized in this invention to lift fuel from the fuel orifice 17to a point where it is available for use when the whirl effect inchamber 5 is not suiicient to cause the required lift. This isaccomplished because the portion of the air pressure through by-pass 34that would be expended in drawing air from the air intake is replaced bythe depression caused by the whirling effect of the leakage around the(n'aclred throttle and thus substantially the full deprf 'ion through 34is available to act upon the i'rrl orifice.

This great depression from beyond the throttle is :ip/plier'.v by meansof the duct 34 opening at 35 beyond the throttle 30, and connectingtangentially with the whirl extension space or annular chan'iber 36formed by a top enlargement of the well 1S extending a short distancelelow the level of the floor 23 of the mixing chamber.

The adjusting tube 19 enters this enlargement and forms an annularopening 37 between the tube and the wall of the enlarge ment 36. whichis in comn'iunication with the center of the mining chamber 5.

The depression or partial vacuum formed beyond the throttle is thusapplied to the space 36. To regulate or adjust the amount of suchdepresion, the duct 39 is provided` leading upward from duct 34 throughthe horizontal duct 40, to and connecting with the duct 28; thusproviding means to allow air from the carburetor inlet 26 to flow intothe duct- 34 for the purpose of regulating the depression in such duct.

Said depression is regulated by means of the needle valve 41. Openingvalve 41 lets air flow into duct 39 and reduces the amount of suctionapplied to the chamber 36. Clos ing 41 cuts off this flow of outside airand allows a heavy suction applied through 34 to operate to increase thedepression in 3G.

An annular clearance 43 formed in the well extension 4 is open at itsupper end into the chamber 36 and sleeve or tube 19 is provided with aperforation 42 that opens into said clearance 43. When the engine isidling the depression in the mixing chamber 5 is not sufficient to causefuel to flow through the jet holes Q4 but there is sulicient depressionto cause fuel to be lifted through the perforation 42 so as to lill theclearance 43. The depression through duct 34 will draw this fuel fromthe clearance 43 and deliver such fuel through opening 35 to beyond thethrottle 30.

-up to the, maximum level 16,

When, however, the throttle is opened, the depression through 34 is verymuch reduced, the depression atthe center of the whirlpool mixingchamber 5, predominates and fuel will be drawn upward to the jet holes24, and delivered directly into the mixing chamber.

To further facilitate the upward movement of the fuel in the bore of thetube 19 to the jet holes 24 when the throttle is suddenly opened, thereis provided the tube 29 communicating with the duct 28 through opening29. Said tube 29 is open to the extension 46 of the well 18 whichextends down to and opens into the cavity 47 of the nut 3. v

The pressure upon the fuel in the constant level chamber 1 is maintainedthe same as that within the carburetor inlet 26 by means of duct 48leading from the duct 28 to the space above the fuel in the constantlevel chamber 1.

In practical operation the carburetor will be started in the usualmanner by closing the choke valve 27 Vmomentarily and then turning theengine over slowly. This will cause y the full force of the suction fromthe engine cylinders to be applied to force an excess of fuel into thecarburetor and thence to the engine.

The fuel will be held in the constant level fuel chamber 1 at themaximum level 16 and will flow through the fuel orifice 17 filling thewell 18 and the bore 25 of the adjusting tube 19, and also .theaccelerating tube 29, and will flow perforation 42 and jet holes 24through the to depressions produced during in response operation.

As soon as the engine starts, the choke valve 27 will be released to theopen position shown on the drawings; after which the carburetor willfunction normally as follows: f

Under load, air enters through the air inlet 26 and passes through thetangential inlet 8 from which it tan gentially enters the mixing chamber5 'and discharges tangentially outward therefrom. through the tangentialoutlet 9 to the engine manifold 11, so as to produce a violent'whirl inthe mixing chamber 5. By regula-tien of the fuel orifice 17 `by screwingthe tube 19 up or down the correct mixture may be obtained and when thespeed of the engine has attained the maximum by regulationof the fuelorifice with the throttle, say half way open, the engine will then takeany other load position without any further adjustment; because thedepression in the center of the whirl mixing chamber, applies bycentrifugal force the proper suction to the fuel at all air velocitiesthrough such whirl mixing chamber, when the fuel jet holes 24' areproperly spaced to maintain a constant relation between the proportionsY of air and fuel.

With the throttle set at idling position, the

`sion in the center of throttle is not entirely closed and the whirldepression in the mixing chamber at such position expressed in a columnof gasoline, becomes less than the distance from the normal fuel level16 to the mixing chamber; therefore it becomes necessary to intensifyhis small depression. This is accomplished as above set forth and thisintensied depression acts as a small vertical addition to the whirlpooleffect. The fuel that is discharged through duct 34 and opening 35 intothe manifold carries with it a large amount of air which comes from themixing chamber down through annular opening 37 so that a fine atomizedspray of fuel and air is injected through by-pass opening into the mainbody of air passing through throttle barrel 33 and past the crackedthrottle 30, into the manifold.

The amount of fuel drawn through 42 is regulated by the adjustment ofthe needle valve 41 which diminishes or increases the suction in theduct 34 imposed by the depression beyond the throttle through the hole35 by regulating the flow of atmospheric air from the carburetor inlet26 through ducts 28. and 39 to the duct 34.

The fuel in the accelerating tube 29 will stand at the normal fuel level16 when the engine is not ruiming; but during the idling period it willassume a position at such a distance below the maximum level 16 v as mayrepresent the pressure necessary to force through the orifice 17 theamount of fuel necessary for idling and to lift such fuel to the opening42.

Tube 29 is open to atmospheric air through the restricted opening 29 andis wide open at the bottom to the fuel in well 18; and before thecorrect amount of fuel for idling will continuously flow through therestricted orifice 17 at any fixed idling speed, the fuel in tube 29must fall that distance below the maximum level 16. which representsfthenecessary suction to lift therfuel through the restricted orifice 17 to,and deliver it through, the opening 42. Y

`When the throttle is opened,'whether for smaller or larger amount, andthe depresincreases in any degree over the idling depression which isimposed by the application of the manifold depression through `the duct34, this additional depression will act to lift fuel in the bore 25 ofthe tube 19 and to deliver it through the jet holes-24. The firstefiectof such additional depression will be to draw fuel fromY tube A29 andtov 'further lower the level of the fuel therein which is constantlyexposed to atmospheric pressure upon its surface; the fuel thusdisplaced in tube 29 being delivered almost instantly to the mixingchamber because there is no restrietion to its flow out of the bottomend, of the tube V29 and the mixing chamberA up through the bore,2r5.-At'l the saine time fuel is started through restricted fuel orifice 17.llhcn, however the de pression has become greater than the distance fromthe level 1G to the lower end of the tube 2f), air Will flow through thetube Q9 and its flou' will he restricted hy the size of the opening Qtl;and said air will bubble through the fuel in the bore 25 of the tube 19furnishing lifting power to help deliver the fuel through the jet holes211 and at 'the same time assisting in atomizing and spraying the fuelinto the mixing chamber.

After the air has begun to flow with the fuel, further opening of thethrottle Will increase the amount of air; therefore at each individualincrease in throttle opening, the opera-tion of tube 29 will momentarilyfurnish an excess of fuel for acceleration; such excess being first, atthe extreme low speeds, in the form of solid fuel from the tube 29itself; and after that, when air bubbles from the bottom of 29 throughthe fuel in 25 there is momonetarily caused by this air, such anincreased displacement oi the fuel in the bore 25 as will hastendelivery of fuel for acceleration of the engine. Thus tube 29 becomes bythe discharge of fuel therefrom and the subsequent hastening of fueldelivery a means of quickly supplying any increased demand for fuelcalled for at each new throttle position.

That is to say, upon sudden opening of the throttle the air rushes intotube 29 faster th an the neu7 depression will produce a new rate of flowof fuel through the orifice 17 the effect of which is that the airdisplaces the fuel already flowing through the bore of the tube 19 andthe Well 18 and its extension., so that this displaced fuel is almostinstantly discharged through the jet holes 24:, furnishingfuel foracceleration, which is imn'iediately followed by the normal addition ofsupply through the fuel orifice 17.

The distribution of the et holes 24 throughout the height of the mixingchamber 5 is necessary in order to prevent the increased depressionprovided by means of the duct 34 and the by-pass hole 35 from lappingover and making a rich spot in the mixture just above the idling speedof the motor.

The perforation 42 provides the idling fuel, and a considerable space isshown between ll2 and the first of the jet holes Q4 so that hole 42 alsoprovides for light loads so that 'when the throttle is opened for higherspeeds, the suction through the holes 24 begins to add Whirlpooldepression to the surface of the fuel in the bore 25 of the tube 19; andas the throttle opens, this Whirlpool depression increases rapidly sothat the fuel rises higher and higher in the tube 19, with increasedopening of the throttle and the successive holes up this tube 19representadditional openings from which the fuel can flow into themixingr chamber under the graduating head imposed by the increasingheight of these holes, for the effect of the suction at all times ismainly against the resistance of the fuel orifice 1?. The depressioninside and outside of the tube 19 is about the same on account of thelarge number of holes giving access to such depression; and the fuel inreality is pulled up in thistube 19 as in a stand pipe and runs outunder force of gravity through the successive perforations as it reachesthem. lVhen the depression is high enough to raise 'the fuel so that itWill flow from all the holes the suction will be direct on the fuel inthe holes, the flow being at all times limited by the fuel orifice 1i'2and in this Way the lapping over of the two sources of depression isavoided and a very economical mixture proportion is maintainedthroughout the whole range of the carburetor and by the distribution ofthese holes 24- the proportions of the mixture at different speeds maybe modified.

By this Whirlpool form of carburetm' the depression used forproportioning the fuel is not added to that of the intake manifold atfull load, and this allows a greater volume of mixture than heretoforepossible to enter the cylinders of the engine so that the power of anengine may be increased as compared to the performance with otherdevices in Which the pressure drop is solely due to vert-ical action.

Te claim:

1. A carburetor comprising a fuel and air proportioning and mixingchamber provided with a tangential inlet and a tangential outlet tosupply air to, and to discharge mixture from said chamber under thesuction of an associated internal combustion engine and to producesuction for supplying fuel to said chamber; a fuel supply chamber; athrottle to control suction through said mixing chamber; an extension tosaid chamber; and means whereby depression on the engine side of thethrottle may be applied to create a sufficient Whirl action of the airin said extension for supplying fuel to said extension and to the engineside of said throttle when the engine is idling.

2. A carburetor comprising a fuel and air proportioning and mixingchamber having a tangential inlet and a tangential outlet to cause aWhirl in the air flowing through the chamber; said chamber having anaxial extension: means to supply fuel to said chamber and to saidextension, said carburetor also being provided with a throttle and witha passage leading from said extension to beyond the throttle forcreating a sufiieient Whirl effect in said extension to supply fuel tosaid passage during idling and slow speed operation.

3. A carburetor adapted to su ply explosive mixture to an internal comustion engine, comprising al fuel and air proportioning and mixingchamber, said chamber having an axial extension open to the center duct;a passage leading from said thereof; inlet and outlet means extendingtangentially outward from said chamber to cause air to flow through, andto cause it to Whirl in, said chamber to produce a depression at thecenter of said chamber for fuel proportioning purposes; means to supplyfuel to said chamber and to said extension; and means to create adepression Within said extension, for the purpose of modifying the Whirleffect in said chamber to supply mixture of correct proportions to theengine when idling.

4. A carburetor consisting of a mixing chamber supplied tangentiallywith air; a constant level fuel chamber below said mixing chamber; aWell in said constant level fuel chamber having a bore; an adjustingtube fitting closely in the bore; a fuel orifice leading into said boreWhich may be opened and closed by said adjusting tube; there being anannular enlargement of the bore around said adjusting tube above theconstant fuel level and opening into said mixing chamber; said annularenlargement being connected beyond the throttle to apply regulatedexcess suction to said enlargement and mixing chamber to control idlingmixture.

5. The combination of a cylindrical mixing chamber having a tangentialair inlet and a tangential mixture outlet; a throttle in said mixtureoutlet; a constant level fuel chamber below the level of said mixingchamber provided vvith a Well that is supplied with fuel through asubmerged orifice; a tube leading into said Well, said Well beingenlarged at its upper end above the fuel level to form an annular spacearound said tube open to the mixing chamber; said annular space beingconnected to a point beyond the throttle'by a passage openingtangentially from said annular' space.

6. The combination of a cylindrical mixing chamber having a tangentialair inlet and a tangential mixture outlet; a throttle in said mixtureoutlet; a constant level fuel chamber below the level of said mixingchamber provided With a Well; that is supplied With fuel through asubmerged orice; a tube fitted in said Well and adapted to open andclose said submerged orice; saidv Well being enlarged at its upper endabove the fuel level to form a space around such tube open to the mixingchamber; said space being connected to a point beyond the throttle by aduct to the atmosphere; and a valve to control said passage.

7 A. carburetor comprising a cylindrical mixing chamber having an axialextension and a tangential air inlet and a tangential mixture outlet; athrottle in said mixture outlet; means to supply fuel on the axis ofsaid mixing chamber; and a passage extending tangentially from saidaxial extension to a point beyond the throttle.

8. A carburetor comprising a constant level fuel chamber and a mixingchamber having an extension through the fuel chamber and provided With aWell; a fuel orifice to supply fuel from said constant level fuelchamber to said Well; a sleeve having fuel nozzles opening into saidmixing chamber above the normal fuel level, said sleeve being adapted todeliver through said nozzles fuel from said well to said mixing chamber;

and an accelerating tube in said sleeve and spaced therefrom, saidaccelerating tube being open at its bottom and submerged in the fuel insaid Well and being open at its top to the atmosphere to admit air tothe Well to assist in delivering fuel from said Well to said mixingchamber.

ln testimony whereof, We have hereunto set our hands at Los Angeles,California, this -llth day of May, 1921.

ROY FRANCIS ENSIGN. ORVILLE HIRAM ENSIGN.

